The Ministry of Manpower (MOM) is probing companies accused of not paying some workers at the Bukit Timah Community Club vaccination centre.
In response to queries from The Straits Times, a spokesman for the ministry and the Tripartite Alliance for Dispute Management confir-med yesterday that MOM had received nine complaints from people who had been engaged as vaccinators and nurses at one of the vaccination centres claiming that they had not been paid.
ST understands that the two companies providing the workers at the centre are the Singapore Ambulance Association (SAA) and Megamanpower.
The ministry said it is helping those affected resolve their payment issues and checking if other vaccinators and nurses are similarly affected.
Eight of the healthcare workers at the centre told ST that they have yet to receive their salary for the month of May, and some for the first week of June.
They are allegedly owed payments of between about $1,300 and over $4,500 since June 15.
The affected workers received a message in a Telegram group chat on June 7 telling them not to turn up for work the next day.
Ms Norshaira Maszlan, 24, who was a vaccinator nurse at the centre, said: "We had shifts lined up for the next few days when we were suddenly told that our contracts were terminated."
Another nurse at the centre who wanted to be known only as Ms Chania, 23, added that she often worked 14-hour shifts and the discovery that she was not being paid was "very frustrating".
The affected workers were also shocked to discover that they were not employees of Megamanpower - despite signing time sheets with its name - but were considered contractors of SAA.
When queried by ST, both companies confirmed that the workers were SAA contractors.
One of the vaccinators at the centre, Mr Hee Jia Yuan, 21, said: "I was quite worried to find out that we signed a contract for service, which meant that we were not protected by the Employment Act.
"This is a problem for people new to the workforce who are unaware of the difference between an independent contractor and an employee."
He and three other vaccinators said this was their first part-time job after serving as medics during national service.
Seven of the workers have since filed police reports against those who recruited them. They told ST that 19 of them are in a Telegram group chat created to seek help in claiming the salaries owed to them.
The vaccination centre is run by Parkway Shenton, which said it had hired Megamanpower to supply workers until early last month.